For a 3 dongle to work the computer or laptop must meet some basic system requirements.

Windows 2000 SP4, Windows XP SP2, Windows Vista OR Mac OS X 10.4 (Tiger) and 10.5 (Leopard) with latest upgrades
The computer's hardware system should meet or exceed the recommended system requirements for the installed version of OS
The computer should also have at least 128MB of RAM, and 50MB of hard disk space available
Display resolution: 800 × 600 or above
A free USB port, so you can plug your modem in
Remember to remove any firewall protection and if it's a work computer they may also need Administrative rights to install the software (tell them to talk to their IT guy)

The USB Modem supports message writing/sending/receiving and group sending (up to 20 contacts at a time). You can manage messages through the dashboard, such as sorting the messages by telephone number or time, plus you can also import/export messages between the SIM/USIM card and a laptop. All through the great user friendly Modem Manager dashboard.